Method of depositing extruded pieces of substances onto individual wrapping sheets and apparatus for carrying out the method

ABSTRACT

A method of cutting pieces of an extruded substance and depositing the pieces on individual wrapping sheets which are being conveyed in the same direction and at the same velocity as the extruded substance is disclosed. The wrapping sheets are fed in an overlapped fashion to the point where the cut off extruded piece is placed onto a wrapping sheet and the conveyor under the sheet onto which the cut piece is being placed is accelerated so that the sheet is disengaged from the overlap with the succeeding sheet immediately before the next cut piece is to be placed onto the next following sheet. An apparatus is disclosed with means necessary for carrying out the method.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of cutting pieces of anextruded substance and depositing such pieces on separate wrappingsheets.

2. The Prior Art

In certain prior art methods of the above mentioned-type the pieces areremoved as they are cut from the extruded string of substance andconveyed by means of separate displacement devices or the like to bedeposited on separate wrapping sheets. The result of such handling ofthe pieces is that the string of substance cannot be extrudedcontinuously.

Another prior art method is disclosed in U.S. Pat. No. 4,094,122according to which the cut pieces of substances continously aredeposited directly onto separate wrapping sheets, so that the transferoperations and displacement devices required for such transfer areavoided. This is achieved by placing the leading end of the substancebeing extruded directly onto the wrapping sheet conveyed by theconveyors a sufficient distance from the leading edge of the wrappingsheet to allow the protruding leading edge of the sheet to form a frontend closure of the finished package, advancing the trailing edge of thewrapping sheet and the leading edge of a succeeding wrapping sheet in amanner so that they form a mutual overlap of a size which is at leastsufficient to form a rear end and a front end closure in the respectivefinished pre-packages, and then by accelerating the leading wrappingsheet together with the cut piece of substance thereon in relation tothe extruding velocity of the substance.

As a result, it is possible to extrude the substance and convey thesheets continuously, as the cut surfaces formed by cutting theindividual pieces of substance are moved away from each other. Thus, theleading ends and the succeeding trailing ends of the wrapping sheets arekept clear of extruded substance and the sheets, each having a piece ofsubstances deposited thereon, are conveyed to a subsequent mechanism forwrapping the single sheet around the pertaining piece of substances andfor folding the front and rear end closures. Moreover, the substance ishandled gently as the pieces need no further handling when depositedonto the sheets.

However, as far as production is concerned, the invention according toU.S. Pat. No. 4,094,122 suffers from certain restrictive drawbacks.Thus, the extruded pieces of substances are cut on the basis of a flowmeasurement, i.e. a measurement of volume, performed within the extruderproper before the product leaves the extruder, which naturally resultsin a certain inaccuracy in the size of the measured pieces ofsubstances, because the measuring signal controlling the cutter allowsmovements in the extruded mass between the point of measurement and thepoint of cutting which is located a certain distance outside the mouthof the extruder. Furthermore, the cut is performed against a solid baseon the conveyor belt at a time when the extruded substance is placedupon the overlap of two consecutive wrapping sheets. As the wrappingsheet with the cut piece of substance thereon has to be acceleratedimmediately after the cut has been made to separate it from thesucceeding underlapping sheet, the invention according to U.S. Pat. No.4,094,122 has clear physical limits as to how much a piece of substancemay weigh in order to make it possible to accelerate and separate thetwo sheets in question, as blocks of extruded substance may cause suchfriction between the overlapping wrapping sheets due to the weightproper of the substance that in practice the machine cannot produce theacceleration pull required to separate the sheets. Indeed, it alsoappears clearly from U.S. Pat. No. 4,090,122 that the inventionparticularly concerns cutting, conveying and wrapping extruded pieces ofsubstances of a very small height with an equal small weight, so thatthe above-mentioned drawbacks will have relatively little significance.

SUMMARY OF THE INVENTION

Therefore, it is the object of the present invention to provide a methodand an apparatus for cutting and depositing extruded pieces ofsubstances onto wrapping sheets during the continuous conveyance of thelatter, the sheets being initially conveyed at a velocity correspondingto the extruding velocity and subsequently accelerated, and the leadingedge of a cut piece of substance being deposited only onto that part ofa wrapping sheet which does not overlap the succeeding sheet so that theoverlapping portion proper between two sheets is not changed with theweight from a piece of substance during the overlap relieving sequenceof the apparatus, thus facilitating this sequence and making it possibleto extrude and wrap pieces of substances having a very high relativenetweight and a great relative height.

The invention will now be explained in further detail with reference tothe drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a partially vertical sectional side view of an embodimentof the apparatus for carrying out the method according to the invention,

FIG. 2 shows a top view of the apparatus shown in FIG. 1, but in whichcertain parts are removed for reasons of clarity,

FIG. 3 shows a sectional view of an amended embodiment of the apparatusaccording to FIG. 1 along the line III--III in FIG. 4, but in whichcertain parts of the apparatus are omitted, and

FIG. 4 shows a top view of the portion of the apparatus shown in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the drawing reference numeral 1 indicates the head of an extruder forextruding a relatively pliable substance, e.g., butter, margarine,cooking fat, or the like. The reference numeral 2 indicates a cuttingmechanism for cutting pieces of the extruded substance, and 3 indicatesthe conveyor means for feeding wrapping sheet, e.g. paper, to the zonein proximity to the discharge end of the head 1.

The cutting mechanism 2 comprises a cutter in the form of anelectrically-heated thread 4 extended between two arms 5, of which onlythe distal one is visible in FIG. 1. These arms 5 are attached to thelowermost end of each leg 6 of a bridge 7. Seen in the verticaldirection, the arms 5 and the legs 6 have a length which is greater thanthe greatest height of the strings of substance which are extruded fromthe head 1, the distance between the legs 6 being wider than thegreatest width of the strings of substance which are extruded. It willbe understood that the head 1 can be provided with different extrudingmouth pieces depending on the size of the string of substance to beextruded.

The bridge 7 is connected to means in the form of a servomotor 8, bymeans of which the thread 4 can be moved upwards and downwards. Thebridge 7 and the servomotor 8 are supported by a shaft 9 extending inthe direction of extrusion and connected to means in the form of anotherservomotor 10, by means of which the thread 4 can be moved forwards andbackwards parallel to the direction of extrusion.

In FIG. 1 the thread 4 has performed an upward movement, thereby causinga piece of substance 14 to be cut. In order to be ready for the next cutthe thread 4 is moved to the left in a distance corresponding to theextruding velocity multiplied by the duration of time of a cut. When thenext cut is to take place, the servomotors 8, 10 are started by animpulse from a sensor 15 which emits the impulse when the piece ofsubstance 14 has obtained the desired predetermined length. As a result,the thread 4 is moved to the right at the speed of the extrudingvelocity and at the same time the thread 4 is moved downwards at avelocity which is selected so that the cut has just taken place when thethread 4 has travelled the same distance to the right as it was movedearlier to the left. The movement of the thread 4 is now repeatedopposite the extruding direction and over the same interval aspreviously, but this time underneath the extruded substance, and thethread 4 is moved upwards when the next impulse is emitted by the sensor15. The two absolute movements performed by the thread (i.e. as seen inthe space) ere indicated with dotted lines 16 and 17 in FIG. 3, in whichthe downward and the upward absolute movements are indicated with 16 and17, respectively. The sensor 15 may, e.g., be an analog or digitaltouch-free distance meter of a known type which is adjustable to thedesired length of the pieces of substances to be cut and which iscapable of measuring such pieces of substances with an accuracy of±0.01% of the length of the single piece, just as the servomotors 8 and10 are adjustable in accordance with any current extruding velocity andthe height and the width of the desired piece of substance. Furthermore,the sensor 15 is mounted in a known way outside the mouth of theextruder 1 at a variable, but known horizontal distance .of the latterand in such a manner that the sensor 15 follows the movements of threadof the cutter 4 and measures the desired length of the pieces ofsubstance 14 and controls the positioning of the thread during itscutting of the pieces.

The conveyor means 3 comprises a drum mechanism 18 consisting of threedrum parts, viz. two end parts 19 and 20 and a middle part 21 mountedbetween them, which middle part is covered in FIG. 2 by an endlessconveyor belt 22 known per se. The drum end parts 19 and 20 are mountednon-pivotally on a shaft 24 which is pitovally mounted in bearings 25,one of the bearings being secured at each side of the apparatus. Themiddle part 21 of the drum is mounted freely pivotally on the shaft 24which is connected to a drive motor 26 in a non specified way. Severalcircular grooves having toothed bottoms are provided in each end part ofthe drum, and a corresponding toothed belt engages with every second ofthe grooves. In the example shown there are eight belts 27 for each endpart 19, 20 of the drum. The back of each belt 27 has a high coefficientof friction in relation to the wrapping material used and protrudesslightly from the pertaining groove. A toothed belt 28 engages with eachof the interjacent grooves and each end part of the drum has seventoothed belts. The back of each belt 28 has a small coefficient offriction in relation to the wrapping material used and protrudesslightly from the pertaining groove. All the belts 27 and 28 run arounda guide roll 29 which is pivotally mounted at each side of theapparatus. The guide roll 29 is located under the drum mechanism 18 andslightly displaced to the right so that the belts 27 and 28 form aninclined track 30 running upwardly to the left between the guide roll 29and the end parts of the drum.

Furthermore, the smooth belts 28 are carried around another guide roll31 which is located in such a manner that the belts have a horizontaltrack 32 which is substantially flush with the bottom side of theextrusion opening of the extrusion head 1.

The conveyor means 3 furthermore include two endless holding belts 34,34 which have relatively smooth exterior surfaces, and each of thesebelts runs around three guide rolls 35, 36, 37 which are pitovallymounted in the frame of the apparatus so that along a part of the guiderolls the exterior surfaces of the holding belts are pushed in adirection towards the exterior surfaces of the belts 27 and 28 along thetrack 30 of the belts and along a part of the belts 27 and 28 engagingwith the end parts 19, 20 of the drum. Furthermore, the belts 34, 34 arepushed towards the belts 27 and 28 along a part of the periphery of theroll 29, the rolls 35 being located under and slightly to the right ofthe roll 29. At the same time, the rolls 29 and 35 cause a sheet feedopening 38 to be formed between the belts 34,34 on the one side and thebelts 27 and 28 on the other side. The belts 34 are adjustedtransversely to the apparatus by way of known means (which are thereforenot shown).

The tensions on the belts 27, 28 and 34 are adjusted in a manner knownper se by means of tightening means (not shown).

The endless conveyor belt 22 runs around the middle part 21 of the drumwhich also functions as an end return roll of the belt 22. The secondend return roll 40 of the belt 22 is pivotally mounted at the oppositeend of the apparatus (as seen in relation to the position of theextruder) and is connected to a motor 41 in a manner not furtherindicated. The roll 40 is located in such a manner that a substantiallyhorizontal track is formed between the roll and the middle part 21 ofthe drum, this track being substantially flush with the bottom side ofthe extrusion opening of the extrusion head.

A support plate 43, see FIG. 2, is located under the track 42. In thelateral direction the plate has protruding portions 44,44 which aretoothed at their front edges to form teeth 45. These teeth project intothe spaces between the belts 28 which are carried around the guide roll31 (only the axis of the roll being shown in FIG. 2), and the outer endsof the teeth 45 are beaded slightly downwards towards the exteriorsurfaces of the end parts 19, 20 of the drum. The middle part of thesupport plate extending below the belt 22 is slightly submerged inrelation to the side portions 44 and extends to the middle part 21 ofthe drum and ends in a sharp edge 47, FIG. 3.

The material to be used for wrapping the extruded pieces of substancesis mounted in the form of a roll 49 at the right end of the apparatus ofFIG. 1 in a known manner. The roll 49 is pitovally mounted in twoconsoles, one of the consoles being shown in FIG. 1. The apparatus isprovided with a buffer or accumulator which in general has the referencenumeral 51 and which consists of three guide rolls 52, 53 and 54, theseguide rolls being pivotally mounted but otherwise unmovably placed, andtwo rolls 55 and 56 which at their ends are pivotally mounted in twoswinging arms 57, one of the arms being visible in FIG. 1. These armsare pivotally connected to the consoles 50 by means of bearings 50, ofwhich only one is visible in FIG. 1. The buffer 51 serves to relieve theroll 49 of sudden pulls in the web of material 60 which is removed fromthe roll 49.

A pair of conveyor rollers 62,63 is mounted between the buffer 51 andthe feed opening 38 between the rolls 29 and 35, viz. one pair ofconveyor rollers is mounted above and one is mounted below the web 60.The bottom rollers 63 are connnected to a motor 64 in a manner notfurther indicated. A pair of rotating scissors are mounted between therollers 62, 63 and the feed opening 38, the scissors having the form ofa counter drum 66 having a smooth surface and a cutter drum 67 locatedabove the former. The exterior surface of the cutter drum is providedwith a longitudinal groove in which a cutter 68 is mounted. The drum 67is connected to a drive motor 70 in a manner not further indicated. Asheet overlapping mechanism 71 is mounted between the rotating scissors66,67 and the sheet feed opening 38.

The sheet overlapping mechanism 71 appears more clearly from FIG. 3. Asmentioned above, FIGS. 3 and 4 show an amended embodiment of theapparatus shown in FIGS. 1 and 2. The only fundamental difference isthat in the amended embodiment according to FIGS. 3 and 4 the guide roll29 of the belts 27 and 28 is omitted. The belts 28 still run around asecond guide roll 31 so that the track 32 is maintained. The frictionbelts 27 are in the form of rings which have toothed inner sidesengaging with the teeth in the bottoms of the pertaining grooves. Forreasons of clarity the belts 27 and 28 are omitted in FIGS. 3 and 4.Thus, the belt track 30 is not used in the amended embodiment and thebottom guide rolls 35 of the holding belts 34 are located immediatelybelow the drum mechanism 18 so that the sheet feed opening 38 is formedbetween the drum mechanism and the guide rolls 35.

The sheet overlapping mechanism, which is known in principle, is thesame in the two embodiments and is clearly shown in FIG. 3 and consistsof a track guide having an upper plate 72 and a lower plate 73 forming alow track guide channel 74 between them which extends in the entirelength of the scissors 66, 67 and has its one end extending towards thegap 75 of the scissors, A channel part 77 also formed between the upperplate 78 and the lower plate 79 is hinged (at 76) to the edges of theplates 72 and 73 facing away from the gap 75. The channel part 77 ispivotable by way of means (not shown) around the hinge 76 as indicatedwith a double arrow 80, The channel part 77 is succeeded by a supportplate 81 at the front end of which a suction box 82 is located and therear end of which extends to the sheet feed opening 38. An feed plate 83having its leading edge (inlet edge) bended upwards in relation to thesupport plate 81 is located above the support plate 81 to receive theleading edge of the wrapping sheet when the sheet leaves the channelpart 77.

The sheet overlapping mechanism 71 operates in the following way:

For each rotation performed by the cutter drum 67 a cut is formedtransversely to the entire web 60 and a sheet is cut free. The trailingedge 88 of the sheet and the leading edge 89 of the web are introducedinto the track guide channel 74, as the leading edge 90 of the free cutsheet 87 being already introduced into the sheet feed opening 38 andbeing in engagement between the exterior surfaces of the friction belts27 and the exterior faces of the belt holders 34. However, the leadingedge 89 of the web 60 is advanced by the conveyor rollers 62, 63. Duringthe passage of the cut through the channel part 78, the channel isturned upwards and when leaving the channel the trailing edge 88 will bedrawn downwards by the suction box 82 and cover the box. Consequentlythe leading edge 89 of the web 60 will move down under the feed plate 83in a certain distance above the trailing edge 88. The conveyor rollers62, 63 are now accelerated by their motor 64, thereby causing theleading end of the web 60 to overlap the trailing end of the sheet 87.In FIG. 3 the reference numeral 92 indicates the overlap formed by thepreceding overlapping operation. Thus, the acceleration of the conveyorrollers is adjusted so that the overlap is provided before the leadingedge 89 of the web reaches the sheet feed opening 38 and has obtained awidth corresponding to at least twice the length of the sheet necessaryto form an end closure of the final pre-package. Once the sheets haveoverlapped, the conveyor rollers 62, 63 are decelerated to their earliervelocity corresponding to the extruding velocity.

The mode of operation of the two hitherto mentioned apparatuses beingalike as to extrusion, cutting of pieces and deposition of the piecesonto the sheets, these parts of the operation will now be described withreference to FIGS. 3 and 4.

When the thread 4 has finished the cutting immediately outside the mouthend of the extruder 1 and the leading end of the piece of substance 14has been placed on the leading part, of the pertaining sheet 93 and thetrailing end of the piece of substance still is located in a certaindistance above the trailing part of the sheet 93, the piece of substance14 is released from the substance string and partly placed upon thesheet 93 conveyed to the right in FIG. 3 by the conveyor belt 22 runningcontinuously at a far greater velocity than the extruding velocity.

Thereby, the piece of substance 14 and the pertaining sheet 93 areremoved from the succeeding piece of substance on the succeeding sheet96 before the piece 14 comes fully to rest on the sheet 93, the sheet 96thus no longer being overlapped by a portion of the sheet 93.

The extruder works continuously and the drum end parts 19 and 20 arelikewise driven continuously and in a manner so that, in relation to theprotruding surfaces of the belts 27, they run with great friction and atthe same velocity as the extruding velocity.

As will appear from FIG. 3, the cut surface 94 just formed at the end ofthe cut string of substance is located substantially immediately abovethe middle of the portion 95 of the succeeding sheet 96 which wasoverlapped earlier by the trailing end part of the sheet 93 which is nowremoved as mentioned above. Consequently the end surface (the cutsurface 94) of the piece of substance will be placed along thetransverse center line of the sheet portion 95, and as a result a freeleading edge zone is formed on the sheet 96, said zone having a lengthcorresponding to half the length of the overlapping part. The piece ofsubstance on the sheet 96 will now be conveyed together while a newpiece of substance 14 is being extruded, as the side portions of thesheet 96 protruding along the end parts 19 and 20 of the drum will beretained between the friction belts 27 and the holding belts 34, thisretention exceeding the conveying effect, of the belt 22.

As the extrusion gradually progresses the retention of the sheet 96 bythe friction belts 27 will gradually be reduced as an increasing portionof the sheet leaves the retention zone of the holding belts 34. Theleading edge of the succeeding sheet will be lifted free of the frictionbelts by the teeth 45 and be conveyed to the side portions 44 of thesupport plate. For reasons of clarity the teeth are omitted in FIG. 4.

When a cut has been terminated, the conveying effect of the belt 22exceeds the retention of the sheet caused by the smooth holding belts 34pressing the trailing portion of the sheet down against the leadingportion of the succedding sheet and by any remaining engagement with thefriction belts 27 as well as by the engagement between the bottom sideof the side portions of the wrapping sheet, which is not weighed down bythe piece of substance, and the exterior surfaces of the portions of thesmooth belts 28 forming the track 28 and which has not yet beenoverlapped by the leading part of the succeeding sheet. The frictionalforce exerted by the sheets in the overlapping zone is only very small.The retention effect caused by the pull strength of the string ofsubstance is eliminated when the string of material is cut and hence thesheet 96 will be conveyed by belt 22 and will now be quickly removed tothe right. The stage shown in FIG. 3, i.e., immediately before removalof sheet, is also shown in FIG. 4 in which the leading edge of thesheet, onto which a deposition of a piece of substance has just takenplace, has the reference numeral 100, the side edges of the sheet 101and 102 and the trailing edge 103 and the piece 14 is shown withdot-and-dash lines. The trailing edge of the succeeding sheet has thereference numeral 104.

For reasons of clarity the teeth 45 along the leading edge 106 of theside portions 44, 44 of the support plate 43 are not shown in FIG. 4 asmentioned above, but it will be understood that in both embodimentsthese teeth will result in that the leading edges of the sheets areeffectively conveyed to the side portions 44, 44 of the support plate 43and they are not carried downwards around the roll 31 by the smoothbelts 28 running around the said roll.

The sheet, the contour lines of which are shown in FIG. 4 as 100, 101,102 and 103, has a size which is the maximum for the apparatuses shown.Also the piece 14 is shown in the drawing with a maximum size.

However, the apparatus can readily be adjusted to other sheet sizes,piece sizes and dimensions of strings of substances, as the mouth pieceof the extruder is interchangeable, and as the apparatus comprises anelectronic calculation and control system (not shown) for regulating thevelocity of the motors 8, 10, 26, 41, 64 and 70, which system alsocontrols the accelerations and decelerations of the motor 64.

In order to avoid having to control the above mentioned adjustments ofthe frictional forces and the pull strength of the extruded string ofsubstance within narrow limits, the apparatus is provided with a slidecloth 106 (FIG. 4) which in the embodiment shown has the same width asthe belt 22. The cloth 106 is mounted on a roll 107 (FIG. 3) and theleading edge of an extended portion of the cloth has the referencenumeral 108. As it clearly appears from FIGS. 3 and 4 the extendedportion of the cloth 106 extends from the roll 107, around the middlepart 21 of the drum and outside the acceleration belt 22 and ends at 108as mentioned above. The cloth consists of a smooth material, e.g.Teflon-coated canvas, and prevents direct contact between the belt 22and the portion of a sheet upon which a piece of substance 14 isextruded. The degree to which the cloth can prevent the contact can beadjusted by rolling out a larger or smaller length of cloth from theroll 107 in turning the latter. The leading edge 108 is loosely placedupon the belt 22, the roll 107 being checked against turning afteradjustment. As the extrusion of substance gradually progresses, anincreasing portion of the sheet will move past the edge 108 of the clothand increasingly get into contact with the belt 22. Thus, the conveyingeffect exerted on the sheet by the belt 22 can be regulated, therebyfacilitating balancing of the above mentioned applied forces.

Even though the above explanations relate to apparatuses in which thetrailing edge of a sheet overlaps the leading edge of a succeeding sheetwhen the sheet is fed to the extruder, the reverse form of overlap mayalso be used, but in that case the holding belts 34 should have a highfriction effect and the belts 27 a low friction effect. If so, thetrailing portion of the sheet will be wedged between the smooth beltsand the leading portion of the succeeding sheet when the sheet isaccelerated just as in the embodiments shown. However, such anembodiment will involve a risk of smudging the leading portion of asucceeding sheet, as this portion will be the upper one nearest to thesubstance when the string of substance is cut.

It will be understood that the belt 22 is intended for conveying thesheets with the pieces of substances to a machine in which the sheetsare wrapped around the pieces in a manner known per se and the endclosures are formed, e.g. by folding.

I claim:
 1. A method of cutting pieces from an extruded substance anddepositing each cut piece into a pertaining wrapping sheet, comprisingfeeding each sheet to a position immediately below an extruder by aconveyor means in such a manner that a trailing edge of a sheet overlapsa leading edge of a succeeding sheet, placing a leading end of the pieceof substance being extruded from a mouth of the extruder directly ontothe wrapping sheet conveyed by the conveyor means and at a certaindistance from the leading edge of the said wrapping sheet to enable theprotruding leading edge part of the sheet to form a front end closure ofthe cut piece, advancing the trailing edge of the wrapping sheet and theleading edge of the succeeding wrapping sheet in a manner so that theyhave a mutual overlap having a length which is sufficient to form a rearend closure of the sheet and a front end closure of the succeeding sheetof the cut piece, and where the sheet and the cut piece of substance arethen accelerated from said position with a velocity higher than theextruding velocity of the substance in order to separate the sheet witha piece of substance thereon from the overlapping pat of the succeedingsheet, wherein the extruded pieces of substances are cut immediatelydownstream of the mouth of an extruder such that the portion of a cutpiece facing away from the mouth of the extruder is deposited onto thepertaining wrapping sheet on that part of the sheet which is notoverlapping the succeeding sheet, whereas the portion of the extrudedpiece closest to the mouth of the extruder is still located at a certaindistance above the sheet and then accelerate the sheet with said highervelocity to separate the sheet from the succeeding sheet before the saidpiece of substance as a whole is deposited onto the sheet and before thesucceeding sheet is in a ready position in relation to the extruder toreceive the succeeding extruded piece of substance.
 2. An apparatuswhich comprises an extruder, a cutting mechanism comprising a cutter,means for causing the cutter to cut the extruded pieces of substances,conveyor means comprising feeding and cutting means and a paperoverlapping mechanism for conveying, cutting and overlapping sheets ofpaper from a paper web to a receiving position for extruding pieces ofsubstances in a track on the upper side of the conveyor means, and meansfor accelerating the sheet with the cut pieces of substances placedthereon with a velocity higher than the extruding velocity so that thesheets are relieved of the overlapping portion of the succeeding sheets,wherein the cutter of the cutting mechanism is mounted immediatelyoutside the mouth of the extruder for cutting pieces of substances usingno solid base for the cutting, and comprising means for making the cutsin subsequent, opposite directions downwards and upwards, respectively,and means for automatically moving the cutter in the same or in theopposition direction as the extruding direction between each unit and independence of a predetermined length of a piece of substance to be cutso as to place said piece of substance with its portion facing away fromthe mouth of the extruder on that part of the pertaining wrapping sheetwhich is not overlapping the succeeding sheet, and with its portionclosest to the mouth of the extruder still located at a certain distanceabove said sheet, and comprising means for accelerating the sheet withthe partly deposited piece of substance at said velocity higher than theextruding velocity so as to separate the sheet from the succeeding sheetbefore the piece of substance as a whole is deposited on the sheet. 3.An apparatus according to claim 2, wherein the cutter of the cuttingmechanism comprises an electrically heated cutting thread.
 4. Anapparatus according to claim 2, including a sensor for directing theelectrically heated cutting thread of the cutter in dependence of thepredetermined length of the piece of substance, the sensor being acontact free distance meter.
 5. An apparatus according to claim 4,wherein the sensor is mounted outside the mouth of the extruder and witha variable, known distance in the horizontal plane between the sensorand the extruder in the direction of extrusion thereby allowing thesensor to measure the desired length of the piece of substance beforebeing cut by the cutter.
 6. An apparatus according to claim 2, whereinthe conveyor means includes a drum mechanism located below the extruder,said drum mechanism comprising two end parts and a middle part, whichend parts are connected to a shaft and the middle part is pivotablymounted in relation to said shaft, the end parts comprising circulargrooves, some of these grooves holding at least a part of a belt so thatthe belts have protruding portions in relation to the grooves, whichportions have a high coefficient of friction in relation to the wrappingsheets, other grooves holding other belts having protruding portionswith a low coefficient of friction, and the friction belts comprise apair of smooth holding belts comprising means for pushing the holdingbelts against the friction belts, and the drum end parts rotate at sucha velocity that the surfaces of the friction belts are moved at the samevelocity as the extruding velocity, and the apparatus comprises anacceleration belt running around the middle part of the drum.
 7. Anapparatus according to claim 6, wherein the smooth belts form a trackrunning parallel with the direction of extrusion.
 8. An apparatusaccording to claim 6, wherein the acceleration belt is supported by asupport plate having protruding side portions along the sides of theacceleration belt, the front edge of the side portions having teethwhich engage between the friction belts forming the track.
 9. Anapparatus according to claim 6, including a slide cloth of a smoothmaterial, an adjustable portion of which is placed upon the accelerationbelt.